Joint for electrical conductors



- arch 24, 1942.

Filed June 5, 1940 1' 8 a 16 20 L 20. 1 18 1 a, 16f- 23 23 I BI G .17 2

- 24 14 lllllllll llllllllll P 15' //YV/YTO@ 2 Sheets-Sheet 1 March 24, 1942. F. M. CUNNINGHAM 1 JOINT FOR ELECTRICAL CONDUCTORS Filed June 5, 1940 2 sheets-sneak 2 Patented Mar. 24,1942

UNITED STATES PATENT OFFICE 2,277,212 7 V i JOINT FOR ELECTRICAL CONDUCTORS I Firmin M. Cunningham, Maplewood, 110.. as-

signor to James B. Kearney Corporation, St. Louis, 110., a corporation of Missouri Application June 5, 1940, Serial No; 338,879

6 Claims.

ical and electrical connection for a onductor member that said conductor member may be capable of movement with respect to an article to which it is joined without afiecting either the "mechanical or the electrical connection therebetween. the predominant object of the invention being to provide a joint of the type mentioned which is capable of performing its intended function in a highly efilcient manner.

While joints of the improved construction disclosed herein are adapted for a number of uses, one important application thereof is in association with bus bars of power stations. As is quite generally known by persons familiar with such matters, bus bars of power stations are frequently quite long and are made up oi numbers of sections which are connected together to provide continuous bus bars, such bus bars usually being supported by porcelain insulators. Due to the fact that bus bars are subjected to expansion and contraction in response to temperature changes, and because said bus bars receive short circuit stresses and shocks which would be likely to do damage to the supporting porcelain insulators if the bus bars were rigid and unyielding, it is necessary to provide Joints between adjacent sections of the bus bars, and between sections of bus bars and articles of electrical equipment, which permit independent movement of the bus bar sections. However, prior to this invention, yielding joints for connecting bus bar sections performed purely: mechanical functions, and independent flexible electrical conductors were employed to provide electrical connection between the adjacent bus bar sections connected mechanically by the yieldable Joints heretofore employed, and between bus bar sections and articles of electrical equipment. t

The outstanding feature of the joint disclosed herein is that it serves the function of providing for such mechanical connection between adjacent bus bar sections, and between bus bar sections and articles of electrical equipment, that permits independent movement of the bus bar sections connected by the joint, and additionally, the improved joint is so constructed and arranged that it provides electrical connection between an adjacent pair of bus bar sections joined by the joint, or between a bus bar section and an article of electrical equipmentso connected. Thus the independent flexible conillustrated in Fig. 1.

Fig. 3 is a cross-section taken on. line 3-4? of Fig. 2.

Fig. s is a cross-section taken on line H of Fig. 2.

Fig. 5 is a cross-section taken on liners-t of Fig. 2. X .Fig. 6 is a the invention.

Fig. 7 is a view partly in side elevation and partly in longitudinal section of the structure illustrated in Fig. 6.

Fig. 8 is a cross-section taken on line 8-8 of Fig; "I. t

In. the drawings, wherein are shown tor the purpose of illustration, merely, two embodiments of the invention, A designates in Figs. 1

plan view of a modified form oi to 5, inclusive, the improved joint generally. In

certain of the views mentioned B designates a section of a bus bar which is of tubular formation, and S designates a screwthreadedterminal stud which is extended from an article E of electrical equipment, a transformer or an oil switch, for instance, (Fig. i). The section or bus bar B and the terminal stud S are spaced apart, as shown in Figs. 1 and 2, and the joint A bridges the space therebetween.

Embracing the end portion of the.section of bus bar E is a clamp t which comprises a pair of arcuate clamping members i and l said clamping members having associated therewith opposed pairs of bolt and nut assemblies 2 which serve in an obvious manner, and as illustrated, to draw the clamping members i and i", into rigid, clamping relation with respect to the outer surface of the bus bar section B. Preferably the clamping members I and I" are provided with arcuate ribs I which contact with the outer surface of the bus bar section B when said clamping members are drawn into clamping relation with said bus bar section Disposed within the end portion of the-bus within said bus bar section s, and said stud-receiving provided on its outer face with annular ribs 3' that contact closely with the inner face of said bus bar section B. The tubular member 3 includes a portion-3* which is an extension of the portion of said tubular portion disposed within the end portion of the bus bar section B, and

said extension is projected outwardly a substantial distance beyond the end of said bus bar section. As shown to the best advantage in Fig. 2

the wall of the extension 3 of the tubular member 3 is of substantially less thickness than the wall of the portion of said tubular member which is disposed withinthe' end portion of the bus bar section B. Obviously the action of drawing the clamping members is and l into tiaht clamping relation withthe outer surface of the bus bar section B by means of the bolt and nut assemblies 2 will cause 'the innerendporflon of the tubularmember I to beisecurely clamped The terminal stud 8 supports anelement e which'includes a split,-stud-receiving end por- V V 2,277,212 bar section B is a tubular member 3' which is with curved outer end portions ii which contact with the inner face of the wall of the tubular portion 4' of the element 4 (Fig; 2). The inner end portions of the contacts II are anchored to the tubular member by an arrangement that includes the use of a ring I! which embraces the .Figs. 2 and 4.

tion 4", and a hollow, tubular portion 4" that is of greater diameter than said stud-receiving portion and extends therefrom toward the adjacent end of the bus bar section B. The end of the hollow tubular portion 4 of the element 4 is open, ,as shown in Fig. 2 and a wall 4 is provided at the opposite end of said hollow, tubular portion 4 whereit joins the stud-receiving portion 4' of said element 4. The stud-receiving'portion 4' of the element 4 has formed therethrough a screwthreaded opening that receives the terminal stud portion 4 is provided with ears 5 having openings through which clamping bolts 8 are extended to clamp the split stud-receiving portion on the terminal stud S and prevent unintended movement of the ele- -merit 4 relative to the stud. S. 7

Supported by each of .the clamping members I! and I is a plurality'o'f contact elements I which are arranged in an arcuate row that foilows the shape'of-the clamping member by which they are supported as shown in Figs. 3' and 4.

The contact elements 1 are in the form of reposite; or inner, end-portions of said contact ele- .ments are anchored to one or the other of the clamping members i' andi".- In order to an- "chor'the contact elements to the clamping members I and I each of said clamping members is provided with a group of radially disposed openings 4 which extend from the inner faces of the clamping members inwardly thereof to points located approximately midway betweenthe inner. andouter facesof said clamping members (Fig.

4). ,The contact elements I are' seated in the inward portions of the openings I and an -arcuate groove 1 (Fig. 2) is formed in each of theclamping members Fund I so that it intersects the openings 4 of theclamping member. Because of this arrangement portions of the contacts I are extended across the arcuate groove I, and the contact elements are secured to theclamping members by forming a weld il in the groove 0,

which fills said groove and secures the contact elements firmly to the clamping members.

The improved joint includes a second group of contacts II in the form of resilient rods which are similar to the contacts I and are supported by the tubular member 3. The contacts II are arrangedin circular formation and are provided 'silient rods having curved, outer end portions I which contact with theouter face of the hollow,

tubular portion-l 'ofi the element 4, and the opportion 3 of the tubular member 3, as shown in of said bus bar section relative to the terminal stud 8. Also, because the contacts I and il exert firm point pressure contact with the opposed faces of the wall of portion 4" of the element 4,

perfect electrical connection is made between the terminal stud S and the bus bar section B which is not disturbed in any manner by independent movement of said bus bar section B.

In Figs. 6, 7, and 8, a modified form of the invention is illustrated according to which the improved joint is supported by an insulator P so that it mechanically and electrically connects a pair of adjacent bus b'ar sections B. The insulator P has fixedly mounted thereon by means of bolts l4 a clamping member l5, said clamping member I being provided with an arcuate clamping face It. Arranged in opposed relation with respect to the clamping member I! is a second clamping-member it which is provided with an arcuate clamping face i6', and arranged between the clamping members I! and I6" is a tubular member I]. The arcuate clamping faces of the clamping members I! and ii contact with the circumferential face of the central portion v of the tubular member ll which is of greater diameter than the end portions ii that extend in opposite directions from said central portion.

The clamping members ii and I are provided with outwardly extended ears I! and li with whichare associated clamping bolts I! that serve to draw the clamping member l6 downwardly-so as to clamp the tubular member l'l. tightly between the-arcuate clamping faces of said clarnp-;

ing members.

iar groups of contacts I. which are anchored to said clamping member I at the inner end por- V tions and are provided at their-outer end portions with. curved portions 2! which contact with the outer surface of the bus bar sections 13';

The contacts I! and 2. are secured to the clamping members II and I in a manner somewhat similar to the manner, already described herein, for attaching the contacts I to the' clamping members ,i' and l of the structure illustrated in Figs. 1 to 5, inclusive. In other words the contacts II and 20 are supported in openings formed in the clamping members it and It so The ring I! is provided at it's inner face with a plurality of notches i! which Extending in opposite directions from. the clamping member I! are groupsof contacts", said contacts being anchored to said'clamping member I! at their inner end portions and be- -ing provided with curved outerendportions ll. which contact with the outer faces of the busbar sections B. Also; extended in opposite di- 'rections from the clamping member ii are simithat portions of the contacts extend across arouate grooves 2i, and these arcuate grooves receive welds 22 which secure the contacts in place.

The joint structure illustrated in Figs. 6, 7 and 8, includes also groups of contacts 23 which are supported by the tubular member I! and extend in o posite directions longitudinally thereof. Each group of contacts 23 is arranged in circular formation and in embracing relation with respect to the outer portions of the tubular member i1. and curved portions 23" are provided at the outer ends of said contacts 23 which contact with the inner faces of the bus bar sections B.

The inner end portions of the contacts 23 are secured to the tubular member H with the aid of companion rings 24 and welds 25 (Fig. 7)

contacts. Because of the welds 25 the rings 24,

contacts 23, and the tubular member I! are secured together to provide a unitary structure.

Obviously, when the structure illustrated in Figs. '6, '7, and 8, is in use, the resilient contacts I9, 20, and 23 serve to provide mechanical support for the bus bar sections B which permits substantial universal movement of said bus bar sections relative to the insulator P. Also, because of the point pressure contact exerted against the outer and inner faces of the walls of the bus bar sections B, perfect electrical connection is provided through the Joint between said bus bar sections B.

said clamp is mounted, said clamp being'disposed in embracing relation with respect to the part of the tubular electrical conductor in which .said portion of said tubular member is located, a

plurality of elongated resilient contact elements supported by said clamp and extended beyond an end thereof and arranged in contact with the outer face of the other ofsaid spaced tubular In th use of both forms of the invention illustrated and described herein the'contacts I and H, of Eigs. 1 to 5, inclusive, and the contacts I9, 20, and 23, of Figs. 6 to 8, inclusive, serve as alinement guides which maintain the alinement of the associated bus bar section or sections. Also, because of the resilient nature of said contactsthey always engage the associated bus bar sections tightly so that there is no opportunity for a chattering action to be developed. Finally the improved jpint permits of independent movement of the bus bar section, orsections. associated therewith without interfering in any manner with the perfect electrical connection provided through the Joint for the bus bar section, or sections, connected mechanically and electrically thereby.

I claim:

1. A joint adapted for use in association with a. pair of spaced tubular electrical conductors, comprising a clamp which is mounted on one of said spaced tubular electrical conductors, a tubular member having a portion which is located within the tubular electrical conductor on which thereof'and arranged in contact with the inner face of said other of said spaced tubular electrical conductors.

2. A joint adapted for use in association with a pair of spaced tubular electrical conductors comprising a clamp which is mounted on one of said spaced tubular electrical conductors, a tubular member having a portion which is located within the tubular electrical conductor on which electrical conductors, and a plurality of elongated resilient contact elements supported by said tubular member and extended from an end thereof and arranged in contact with the inner face of said other of said spaced tubular electrical conductors, said elongated resilient contact elements being provided with curved contacting portions at points where they contact with the outer and inner faces of said other tubular electrical conductor.

3. A joint for mechanically enga ing and electrically connecting an electrical conductor, comprising in combination a tubular electrical con-- ductor, a support, a contractile clamp mounted on said support, a member having a portion engaged within said clamp for securement to said support by contractile clamping action of said clamp, a plurality of elongated resilient contact elements supported by said clamp and extended beyond an end thereof and arranged in contactwith the outer face of said tubular electrical conductor, and a plurality of elongated resilient contact elements supported by said member and extended from an end thereof and arranged in contact with th inner face of said tubular elec trical conductor.

4i A Joint for mechanically engaging and electrically connecting an electrical conductor, comprising in combination a tubular electrical conductor, a support, a contractile clamp mounted on saidsupport, a tubular member having aportlon engaged within said clamp for secuiement to said support by contractile clamping action of said clamp, a plurality of elongated resilient contact elements supported by said clamp and extended beyond an end thereof and arranged in contact with the outer face of said tubular electrical conductor, and a plurality of elongated resillent contact elements supportedby said member and extended from an end thereof and arranged in contact with the inner face of said tubular electrical conductor.

5. A joint for mechanically engaging and electrically connecting an electrical conductor, comprising in combination a tubular electrical conductor, a support, a contractile clamp mounted on said support, a member having a portion engaged within said clamp and substantially embraced thereby for securement to said support by 'contractile clamping action of said clamp, a plurality of elongated resilient contact elements supported by said clamp and extended beyond 'an end thereof and arranged in contact with the outer face of said tubular electrical conductor, and a plurality of elongated resilient contact elements supported by said member and extended from an end thereof and arranged in contact with the inner face of said tubular electrical conductor.

6. A Joint for mechanically engaging and electrically connecting an electrical conductor, comprising in combination a tubular electrical conductor, a support, a contractile clamp mounted on said support, a member having a portion engaged within said clamp for securement to said support by contractile clamping action of said clamp, a plurality of elongated resilient contact 2,277,212 elements supported by said clamp and extended trical conductor; said elongated resilient contact elements being provided with curved contacting portions at the points where they contactwith the outer and inner faces of said'tubiiler electrical conductor.

FIRMIN M. CUNNINGHAM. 

